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    nektos

    nektos/act

    #51 this week

    Run your GitHub Actions locally 🚀

    devops
    ci
    github-actions
    golang
    Go
    MIT
    72.0K stars
    2.0K forks
    72.0K GitHub watchers
    Updated 9/14/2026
    View on GitHub

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    Use Cases & Benefits

    • Runs GitHub Actions workflows locally using Docker to simulate GitHub's environment and filesystem.
    • Provides fast feedback by allowing developers to test and debug GitHub Actions without pushing commits.
    • Use for speeding up CI/CD workflow development by running and iterating on GitHub Actions locally.
    • Use for replacing Makefiles by leveraging existing GitHub Actions as local task runners.
    • Use for integrating local GitHub Actions testing directly within VS Code via compatible extensions.

    About act

    act-logo

    Overview push Go Report Card awesome-runners

    "Think globally, act locally"

    Run your GitHub Actions locally! Why would you want to do this? Two reasons:

    • Fast Feedback - Rather than having to commit/push every time you want to test out the changes you are making to your .github/workflows/ files (or for any changes to embedded GitHub actions), you can use act to run the actions locally. The environment variables and filesystem are all configured to match what GitHub provides.
    • Local Task Runner - I love make. However, I also hate repeating myself. With act, you can use the GitHub Actions defined in your .github/workflows/ to replace your Makefile!

    [!TIP] Now Manage and Run Act Directly From VS Code!
    Check out the GitHub Local Actions Visual Studio Code extension which allows you to leverage the power of act to run and test workflows locally without leaving your editor.

    How Does It Work?

    When you run act it reads in your GitHub Actions from .github/workflows/ and determines the set of actions that need to be run. It uses the Docker API to either pull or build the necessary images, as defined in your workflow files and finally determines the execution path based on the dependencies that were defined. Once it has the execution path, it then uses the Docker API to run containers for each action based on the images prepared earlier. The environment variables and filesystem are all configured to match what GitHub provides.

    Let's see it in action with a sample repo!

    Demo

    Act User Guide

    Please look at the act user guide for more documentation.

    Support

    Need help? Ask in discussions!

    Contributing

    Want to contribute to act? Awesome! Check out the contributing guidelines to get involved.

    Manually building from source

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